Ladder and method of preparing rungs and rails thereof



' Oct. 11,1927. 11,644,694

A. V. ROWE LADIIDEIR AND METHOD OF BREPARING RUNGS AND RAILS THEREOF Filed 'April 9. 1924 UNETEE S 1 F T 1,644,694 a F F I c E.

ALVIN V. ROWE, OF GALESBUBG, ILLINOIS.

LADDER AND METHOD or rnnrniiins Runes AND RAILS rrnnnnor.

Application filed April 9,

This invention has reference to the method of preparing the rungs, tenons and the mortises or openings in the side rails of wooden ladders to close the pores of the wood against the absorption of moisture, to prevent the rotting of the wood and to the resulting ladders made inaccordance with my method.

The method consists in searing the surface and shoulders of the tenons and the rungs immediately adjacent such shoulders, and.

also the mortises or openings in the side rails and the faces of the side rails surrounding such mortises; such searing being for the purpose of, first-smoothing the parts to make a more perfect fit, and second-'to close the pores" in the wood to seal the pores against the absorption of moisture and thereby prevent v the rotting of the wood Where these parts are joined.

The invention has for a further object to construct a ladder, the side-rails of which converge, wherein the mortises or openings through the side rails for the tenons of certain of the rungs are at an" acute angle to the inclination of the side rails, and where, the surfaces of the rails surrounding the mortises are provided with counterbores to receive the shouldered ends of the rungs; such counterbores, due to the inclination of the rails forming a pronounced shoulder at one side of the rungs and disappearing in the surface at the other side to insure an absolutely square fit of the face of the v shoulders of the rungs with the basesof said counterbores. The mortises or openings being bored clear through the rails and the ends of the tenons presenting a button effect on the outside of the rails. I

That the invention may be more fully understood, reference is had to the accom-i panying drawings, illustrating a preferred embodiment of the invention, in which Figure 1 is a face view of a ladder embodying my invention;

Figure 2 is a detail in section showing part of a side rail, rung and tenon and showing the searing of the parts; I

Figure 3 is a view of the rail in Figure 2, the rung being omitted;

Figure 4 is an end view illustrating the button effect of the rung and tenon;

Figure 5 is an inside face View of a rail;

Figure 6 is an outside face view of arail;

Figure 7 is a detail sectional view illustrating a grip for the lower ends of the rails, and

1924. Serial No. 705,225.

Figure 8 is a bottomplan view ofsaid grip. v

Like characters of reference denote correspondmg parts throughout the figures.

vVooden ladders aremade single and .ex-

tension and are composed .of side rails connected by rungs. Insingle ladders the side rails are preferably taperedat the rate of about one quarter inch to the foot. And in extension ladders, the. lower part, for; the first three or four feet the rails are tapered will creep in andsoon decay the wood and the ladders finally become wabbly and loosejointed. It is to obviate these defects that my invention is directed. y 1 :In Figure 1 a section of' 11 extension ladder is shown, including vthe side rails 1 and therungs 2. It will be observed that the lower end of the ladder, for a portion of its length is tapered at about one inch to the foot, In other words the side rails converge from theirlower ends upward.

The side rails 1 at pre-determined points are provided with mortises or openings 3 bored completely therethrough. In thetapered ends of said side rails these openings are preferably at an acute angle to the inclination of such rails, and in the remaining portions of said rails these mortises or openings are disposed at right angles to said rails. The arrangement of the mortises or openings in the tapered ends of theside rails, illustrates substantially the construction of mortises or openings in the tapered rails of ordinary single ladders. The opposite, inside and outside faces of the rails at the mortises or openings 3 are counterbored, as at 4 to provide ring-like-seats on one face of each rail for the shouldered ends of the rungs and on the other face to present a button effect of the ends of the tenons protruding through said mortises or openings and to present a significant marking for the ladders made in accordance with the invention. These counterbores, especially in the tapered rails, are concentric to the mortises v or openings 3, and they being at an acute angle to the inclinations of the rails form pronounced shoulders, as at 5 and merge into the surfaces of the rails, as at 6 Such structure, results in giving an equal bearing for the rungs all around the shoulders of the tenons and insures an absolutely square fit of the shoulders of the t'e'nons of the rungs against the inside faces of the rails, see Figure 2;

The rungs 2 are rovided at their opposite ends w ithtenon-s and squared shoulders 8. The ends of the 'tenons having a buttonlike appearance; as at 9.

'The mortises or openings 3 as Well as the eounter-bores 4 are seared by the use of some "suitable tool or machine, and likewise the complete tenons 7, the face of the shoulders 8 and that portion of the ends of the rungs 2 immediately adjacent the shoulders 8 are also seared by some suitable tool, the effect of which is to smooth as Well as insulate the surfaces so treated, and in so doing to e ose the pores in the Wood which will act to seal the 'saime against the absorption of moisture and thereby prevent the wood from rotting, insuring a more perfect fit and increase the'life or the ladder. I prefer that the counterbores 4 in the rails shall be of a greater diameter than the rungs and te'no'nswhich Willp rotect the surfaces of the rails surrounding the rungs on the inside faces of the rails and the surfaces of the rails surrounding the rungs on the out side faflces of the rails, and said outside co'unterbores and buttonends of the tenons giving a distinctive appearance to ladders made in accordance with my invention.

The tenons may, if it is deemed desirable,

be secured in the side rails of the ladder by means of galvanized cement coated nails passed through the rails and openings 10 in the tenons, see Figure 2.

The lower ends 'of the rails 1 are cut off at an angle, as at 1 1, Which become the fiat faces of the ends of the rails to rest on the ground When 'the'ladder' is inclined against an ob ect, and to provide asuction gr p to prevent slippage of the rails such faces 11 have attached thereto the rubber plates 12 having vacuum cups 13 Whichgrip the sur face on Which they rest.

hat I claim is A Wooden ladder including side rails, hav

'ing openings there'threug'h and counterbored seats in the opposite faces thereof, the openlngs, and the seats being searedtoclose the pores in the Wood and rungs having shouldered tenons fitted in said openings, the tenons, the shoulders, and the peripheries of the rungs adjacent the shoulders being each I 

